:root {
  /* Colors */
  --color-bg: #ffffff;
  --color-text: #000000;
  --color-text-muted: #666666;
  --color-border: #e0e0e0;
  --color-accent: #000000;
  --color-accent-hover: #333333;
  --color-error: #ff3333;
  
  /* Typography */
  --font-main: 'Instrument Sans', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-display: 'Instrument Serif', serif;
  
  /* Spacing */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 48px;
  --space-2xl: 80px;
  
  /* Radii */
  --radius-sm: 4px;
  --radius-md: 8px;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-main);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.5;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
}

main {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-lg);
  width: 100%;
}

.login-container {
  width: 100%;
  max-width: 400px;
  animation: fadeIn 0.8s ease-out;
}

.brand {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-xl);
  justify-content: center;
}

.brand-icon {
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.brand h1 {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 400;
  letter-spacing: -0.02em;
}

.login-card {
  border: 1px solid var(--color-border);
  padding: var(--space-xl) var(--space-lg);
  border-radius: var(--radius-md);
  background: white;
}

.login-header {
  margin-bottom: var(--space-lg);
  text-align: center;
}

.login-header h2 {
  font-size: 1.25rem;
  font-weight: 500;
  margin-bottom: var(--space-xs);
}

.login-header p {
  color: var(--color-text-muted);
  font-size: 0.875rem;
}

.form-group {
  margin-bottom: var(--space-lg);
}

.form-label {
  display: block;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  font-weight: 600;
  margin-bottom: var(--space-sm);
}

.form-input {
  width: 100%;
  padding: var(--space-md);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  font-family: var(--font-main);
  font-size: 1rem;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
  outline: none;
}

.form-input:focus {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 2px rgba(0,0,0,0.05);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  padding: var(--space-md);
  background: var(--color-accent);
  color: white;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.2s ease, transform 0.1s ease;
  text-decoration: none;
}

.btn:hover {
  background: var(--color-accent-hover);
}

.btn:active {
  transform: translateY(1px);
}

.login-footer {
  margin-top: var(--space-lg);
  text-align: center;
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

.login-footer a {
  color: var(--color-text);
  text-decoration: none;
  font-weight: 500;
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s ease;
}

.login-footer a:hover {
  border-bottom-color: var(--color-text);
}

/* Animations */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Responsive */
@media (max-width: 480px) {
  .login-card {
    border: none;
    padding: var(--space-lg) 0;
  }
}